7. When we started this build we didn’t realize that the RHS block calls for a specific gasket to work with its interlocking sleeve design. Because of this we used the common .050-inch GM MLS gasket thickness in our math for compression. The Fel-Pro-made RHS gasket (PN 549402-L(R), $140 each) comes in with a compressed thickness of .036-inch, which bumped our compression up a bit. This is important to keep in mind when ordering pistons.